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N Muthukumar

Publications and source records attributed to N Muthukumar.

32 records · Page 2Linked to original sources
PubMed1998

Stereotactic radiosurgery for chordoma and chondrosarcoma: further experiences.

PURPOSE: Skull base chordomas and chondrosarcomas pose management challenges owing to their critical location, locally aggressive nature, and high recurrence rate despite multimodality treatment. We used stereotactic radiosurgery as primary or adjuvant therapy to achieve safe and effective therapeutic irradiation. METHODS AND MATERIALS: At an average of 4 years (range 1-7), we evaluated 15 patients (nine with chordomas and six with chondrosarcomas) who had gamma-knife radiosurgery as an adjunct (13 patients) or as an alternative to microsurgical resection (two patients). Patient age varied from 7 to 70 years (mean 38). There was a distinct male preponderance (2:1). Thirteen patients had undergone between one and four resections. Using conformal radiosurgical planning, a maximum tumor dose of 24-40 Gy (mean 36) and a tumor margin dose of 12-20 Gy (mean 18) was given to a mean tumor volume of 4.6 ml. RESULTS: Eight patients showed clinical improvement, three remained stable, and four died. Two of the four patients who died had tumor progression remote from the radiosurgery volume; two patients died of unrelated disorders. Among 11 surviving patients, follow-up imaging showed a reduction in tumor size in five, no further tumor growth in five, and an increase in the size of the tumor in one. The patient with further tumor growth after radiosurgery subsequently underwent repeat resection. CONCLUSION: Despite the formidable management challenge posed by these neoplasms, our long-term evaluation has shown that radiosurgery is a safe and effective treatment for patients with small volume tumors.

Adolescent↗
PubMed1998

Stereotactic radiosurgery for tentorial meningiomas.

Radical microsurgical resection is the procedure of choice for tentorial meningiomas. Despite advances in microsurgery, tentorial meningiomas continue to challenge surgeons and patients. To evaluate the response of tentorial meningiomas, we evaluated 41 patients who had Gamma knife stereotactic radiosurgery during a 9 year period. Patient age varied from 32 to 79 years. Headache, trigeminal neuralgia, or facial paraesthesia were the most common presenting symptoms. Sensory deficits in the distribution of the trigeminal nerve were the most common finding. Eighteen patients (44%) had undergone between 1 and 5 (mean, 1.9) resections prior to radiosurgery; 23 had tumors diagnosed by neuroimaging. The average tumor diameter in this series was 20 mm. The maximum tumor dose varied from 24 to 40 Gy (mean, 30.5 Gy), and the tumor margin dose varied from 12 to 20 Gy (mean, 15.3 Gy). During the average follow-up interval of 3 years (range, 1-8 years), 19 patients had clinical improvement, 20 remained stable, and 2 patients deteriorated. Follow-up imaging showed a reduction in tumor size in 18 patients, no further tumor growth in 22, and an increase in tumor size in one (overall tumor control rate of 98%). Stereotactic radiosurgery using the Gamma Knife was a safe and effective primary or adjuvant treatment for patients with tentorial meningiomas.

Adult↗
PubMed1998

Retinocephalic vascular malformation: case report.

A 12-year-old boy who presented with unilateral blindness and exophthalmos was found to have retinocephalic vascular malformations (Bonnet-Dechaumme-Blanc syndrome or Wyburn-Mason Syndrome). The ophthalmic, neurological and radiological findings of this rare syndrome are discussed.

Arteriovenous Malformations↗
PubMed1998

Tentorial venous sinuses: an anatomic study.

OBJECTIVE: Certain neurosurgical procedures require sectioning of the tentorium cerebelli. The presence of venous sinuses within the tentorium makes these procedures difficult. The aim of this study was to investigate the incidence, size, location, configuration, and pattern of venous drainage of these sinuses. METHODS: The tentorium cerebelli was studied in 80 fresh cadavers. After the skull cap and the supratentorial portion of the brain were removed, the tentorium was inspected for the presence of venous sinuses. Their location, size, configuration, and pattern of venous drainage were noted. Subsequently, the infratentorial structures were removed via the tentorial incisura. The tentorial sinuses were again studied. In certain cases, the sinus was opened and a probe passed inside to confirm its presence. RESULTS: The tentorium cerebelli was revealed to contain sinuses in 86% of the cadavers. These sinuses were classified into the following three types: Type I sinuses constituted 25% of the total and were most often located in the medial one-third of the tentorium. They were larger than the other types, frequently occurring with a branching "stag-horn" configuration and a tendency to drain into the straight sinus, the torcular herophili, and the medial one-third of the transverse sinus. Type II sinuses constituted 25% of the total and were most often located in the lateral one-third of the tentorium. They were smaller than the other types, and tended to drain into the duction of the transverse sinus and superior petrosal sinus and into the lateral one-third of the transverse sinus. Type III sinuses constituted 50% of the total and were located in the medial one-third of the tentorium. Their size ranged from small to medium. Unlike Type I sinuses, no branching pattern was observed. These sinuses tended to drain into the straight sinus, the torcular herophili, and the medial one-third of the transverse sinus. In the present study, the medial one-third of the tentorium was observed to be the most vascular part. No venous sinus was observed in the anterior part of the tentorium. CONCLUSION: Venous sinuses are common in the tentorium cerebelli. In this study, they were observed in 86% of the cases. They can be classified into three types, based on their location, size, configuration, and pattern of drainage. The medial one-third of the tentorium is the most vascular part. A knowledge of these sinuses may be helpful while sectioning the tentorium. The importance of these sinuses in treating vascular and neoplastic diseases of the brain is highlighted. A brief review of the embryology of these sinuses is also presented.

Cadaver↗
PubMed1997

Primary calvarial meningiomas.

Four patients who presented with calvarial masses which subsequently turned out to be meningiomas are presented. Three of these lesions presented with scalp swellings and osteolytic lesions on the plain radiographs. These three lesions had eroded the inner and outer tables of the skull with soft tissue components in the extradural plane. The fourth lesion was an entirely intraosseous meningioma. The clinical, radiological and pathological findings are discussed, and the relevant literature is reviewed.

Adolescent↗
PubMed1997

Traumatic haemorrhagic optic neuropathy: case report.

We report a case of visual loss following haemorrhage into the optic nerve sheath following head trauma. The patient showed improvement in visual function following decompression of the optic nerve sheath and evacuation of the haematoma.

Child↗
PubMed1996

Basal ganglia-internal capsule low density lesions in children with mild head injury.

I report my experience with 14 children with mild head injury who presented with a distinct clinico-radiological syndrome. Twelve of these children were less than 18 months of age. A fall was the most common mode of injury. These children presented with immediate onset of hemiparesis. CT showed a low density lesion in the region of the basal ganglia-internal capsule. All these children made a good recovery within 2 weeks. The pathogenesis of this particular clinico-radiological syndrome is discussed.

Basal Ganglia↗
PubMed1996

Surgical treatment of nonprogressive neurological deficits in children with sacral agenesis.

I report my experience with 10 children with varying degrees of sacrococcygeal agenesis. There were four children with total agenesis and four with partial agenesis. All of these children had neurological deficits that had been static since birth. Radiological evaluation of these children revealed the presence of tethered cord in two children and tethered cord with lipomeningocele in one. Surgical correction of these intraspinal anomalies led to the improvement of urinary incontinence in these children. This report highlights the fact that children with sacral agenesis and nonprogressive neurological deficits may have correctable intraspinal anomalies, and hence all of the children with sacral agenesis should be evaluated for the presence of treatable intraspinal anomalies.

Child↗
PubMed1993

Influence of basal cisterns, midline shift and pathology on outcome in head injury.

The relationship of outcome to the basal cisterns, midline shift and pathology as seen on initial CT scan was assessed in 107 moderate and severe head injured patients. The mortality rates were 82 cases (76%) and 29 cases (27%) among those with obliterated and normal basal cisterns, and 74 cases (69%) and 42 cases (39%) when the midline shift was present and absent, respectively. The state of the cisterns and midline shift was correlated with the type of intracranial pathology and Glasgow Coma Scale (GCS) scores. The state of the cisterns and midline shift was more important for those with single contusions and intra-cerebral haematoma (ICH) than for those with multiple lesions, extradural haematoma, subdural haematoma, diffuse cerebral oedema and normal CT scan. The state of the above two parameters when correlated with GCS score, showed that they were important for those with higher GCS scores. This indicates that the status of the cisterns and midline shift is correlated with the type of pathology and GCS score rather than these parameters taken alone in prediction.

Adult↗
PubMed1992

Sacral agenesis occurring in siblings: case report.

We report a rare incidence of sacral agenesis occurring in siblings. One of our patients had a low-lying conus, and untethering of the cord in the area of the filum terminale led to improvement in urinary symptoms. The need for aggressive investigation of patients with sacral agenesis and static neurological deficits is discussed.

Child↗